chore: Refactor usages of File. and Directory. to use wrappers

[tippmar-nr]

• Refactors usage of File. and Directory. to use IFileWrapper and IDirectoryWrapper instead.
• Adds methods to IFileWrapper and IDirectoryWrapper as needed with default pass-through implementation.
• Adds a static Instance property to FileWrapper and DirectoryWrapper for use in static methods
• Removes IFileReaderWrapper and moves implementation to IFileWrapper and FileWrapper
• Does not alter any unit tests (aside from required argument refactoring); this change simply reduces friction for future unit tests that may need to mock file and directory operations.
• Did not attempt to refactor usages of Path. as that usage is ubiquitous throughout the codebase and we haven't previously had a need to mock that functionality for tests.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 48.64865% with 19 lines in your changes missing coverage. Please review.

Project coverage is 82.22%. Comparing base (8c70ed2) to head (b990bc1).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
.../NewRelic/Agent/Core/Config/ConfigurationLoader.cs	28.57%	5 Missing ⚠️
...t/NewRelic/Agent/Core/AgentInstallConfiguration.cs	0.00%	3 Missing and 1 partial ⚠️
.../NewRelic/Agent/Core/Logging/LoggerBootstrapper.cs	33.33%	1 Missing and 1 partial ⚠️
...gent/NewRelic/Agent/Core/RuntimeEnvironmentInfo.cs	0.00%	2 Missing ⚠️
.../NewRelic/Agent/Core/Utilities/ExtensionsLoader.cs	0.00%	2 Missing ⚠️
.../Agent/NewRelic/Agent/Core/Utilities/SystemInfo.cs	50.00%	2 Missing ⚠️
.../Configuration/AppSettingsConfigResolveWhenUsed.cs	0.00%	1 Missing ⚠️
...ent/Core/Instrumentation/InstrumentationWatcher.cs	66.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3058      +/-   ##
==========================================
+ Coverage   82.18%   82.22%   +0.04%     
==========================================
  Files         477      477              
  Lines       30623    30625       +2     
  Branches     3426     3426              
==========================================
+ Hits        25166    25180      +14     
+ Misses       4658     4644      -14     
- Partials      799      801       +2     

Flag	Coverage Δ
Agent	83.27% <48.64%> (+0.04%)	⬆️
Profiler	72.51% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...wRelic/Agent/Core/Config/BootstrapConfiguration.cs	98.86% <100.00%> (ø)
...NewRelic/Agent/Core/Config/ConfigurationTracker.cs	100.00% <100.00%> (ø)
...ewRelic/Agent/Core/Utilization/UtilizationStore.cs	85.36% <100.00%> (ø)
...gent/NewRelic/Agent/Core/Utilization/VendorInfo.cs	90.00% <100.00%> (+0.86%)	⬆️
...Core/WireModels/LoadedModuleWireModelCollection.cs	89.43% <100.00%> (ø)
.../Configuration/AppSettingsConfigResolveWhenUsed.cs	0.00% <0.00%> (ø)
...ent/Core/Instrumentation/InstrumentationWatcher.cs	33.33% <66.66%> (+1.25%)	⬆️
.../NewRelic/Agent/Core/Logging/LoggerBootstrapper.cs	77.57% <33.33%> (ø)
...gent/NewRelic/Agent/Core/RuntimeEnvironmentInfo.cs	16.84% <0.00%> (ø)
.../NewRelic/Agent/Core/Utilities/ExtensionsLoader.cs	32.87% <0.00%> (ø)
... and 3 more

... and 2 files with indirect coverage changes

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[nrcventura]

Is there value in making these changes if we do not add unit tests to the code, or do not plan to add unit tests to the code? If we do plan on adding unit tests, and this is just the first step in that process, then I think it is fine. Otherwise, I do not think we should make these changes.